No, I dont have Bob. I try to get one if it is locally available. But what is the use of it?
That one is a little expensive if you don't use it a lot,and you might get a better deal on ebay or Amazon. I suggested it only because SPL (sound pressure level) is easier to interpret. There are standards expressed in db (decibels) the relate to real word situations. Loud, soft and such terms are all relative.
If you choose to, you can correlate your volume settings to a more scientific standard - also keyed to distance from the source of the sound. The efficiency and design of the speakers vary so much, it can be useful to know at what SPL in a given system the clipping occurs. There are also all the lab/hardware devices that can be even more informative - but that's still above my pay grade for now.
It obviously is not something that will influence the operation of the amp, and is completely optional - but is fun to have around.
If you choose to, you can correlate your volume settings to a more scientific standard - also keyed to distance from the source of the sound. The efficiency and design of the speakers vary so much, it can be useful to know at what SPL in a given system the clipping occurs. There are also all the lab/hardware devices that can be even more informative - but that's still above my pay grade for now.
It obviously is not something that will influence the operation of the amp, and is completely optional - but is fun to have around.
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Got my curiosity up so I went Googleing for "Software SPL Meter".
Found a couple possibilities:
REW - At least it looks impressive.
Audio Tool - Android app.
I downloaded both and will report in the morning.
Found a couple possibilities:
REW - At least it looks impressive.
Audio Tool - Android app.
I downloaded both and will report in the morning.
cool
not huge, but noticeable! that is the main point.So, at the end a difference was there...
Mine 10k log Dale attenuator was set to 15th step out of 23 when I compared the caps. That was quite loud, not 80% of the scale, though more than a half. Do you use linear pot or log? It should be fine with the last one as we don't have linear hearing.
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The Audio Tool app is really quite remarkable. It was nice enough that I upgraded to the paid version ($6.95). More useful real time information than the dedicated RS unit I've been using. I don't own an iPhone or iPad but I'm sure there is an equivalent available.
Just a reference - with JRiver flac files using the program volume control - playing through a Mini2496 DAC - pushing the Sunflower speakers, there is no clipping at max settings. Just very very loud
Just a reference - with JRiver flac files using the program volume control - playing through a Mini2496 DAC - pushing the Sunflower speakers, there is no clipping at max settings. Just very very loud
For volume control a log one should be used.
IMHO it explain why your volume goes up so quickly...
It is more likely that the system gain is too high.
A CDP putting out ~2.2Vac @ 0dBfs into an amplifier with 31.77times gain (+30dB) has the potential to give an output of 98Vpk if the amp supply rails were +-105Vdc.
Simply ludicrous to expect anything other than "just turned on" when using a normal potentiometer and bonkers to consider a linear law potentiometer.
read
http://www.diyaudio.com/forums/diyaudio-com-articles/186018-what-gain-structure.html
A CDP putting out ~2.2Vac @ 0dBfs into an amplifier with 31.77times gain (+30dB) has the potential to give an output of 98Vpk if the amp supply rails were +-105Vdc.
Simply ludicrous to expect anything other than "just turned on" when using a normal potentiometer and bonkers to consider a linear law potentiometer.
read
http://www.diyaudio.com/forums/diyaudio-com-articles/186018-what-gain-structure.html
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For volume control a log one should be used.
IMHO it explain why your volume goes up so quickly...
Can you refer a good one? I dont think the volume gone up with minimum increase. Its loud but not that much loud. I will check again.
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I bought this one. Should be even better then Alps as it's of ladder type, but I didn't compare though have them both.
One bad common thing about China attenuators, is that the 1st one I got couple of month ago was completely defective, the other one had a wrong DALE resistor soldered on both channels. So I had to replace them with Vishay, didn't want to spend another month of waiting for the 3rd one
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I have the same Bob. Its so nice. I am using it with Siva's MyRef. I felt like it rolled off the high frequency. I planned to use it with FE but i auditioned Siva's system where he used plain philips carbon potentiometer and changed my mind gone to Alps. I will try the mentioned attenuator. May be off topic, I even had clipping with siva's MyRef, but only at 80% volume. It is really louder.
The amps are built and working from September, some photos are attached below.
They are a far cry from the gainclone I had and considering that the power stage is practically the same, I guess the project make a difference.
The most obvious aspect is the control of low frequencies that now are more consistent with the rest of the spectrum, before the bass*joined to standing waves of the room, making it sound very artificial.
Now the modal resonances remain, but the bass is still nice, however I would add a few pictures with the rock wool to dampen the reverberation of the room.
I've attached also a picture with a graph of RT60 of right channel (RT60 is the time required for reflections of a direct sound to decay by 60 dB below the level of the direct sound.)
Then I perceived a greater involvement with the voices, thanks the great detail and dynamics.
In conclusion, the My_Ref_FE have really satisfied me, the transition from gainclone was not a side-grade, as initially thought.
Thanks,
Roberto
They are a far cry from the gainclone I had and considering that the power stage is practically the same, I guess the project make a difference.
The most obvious aspect is the control of low frequencies that now are more consistent with the rest of the spectrum, before the bass*joined to standing waves of the room, making it sound very artificial.
Now the modal resonances remain, but the bass is still nice, however I would add a few pictures with the rock wool to dampen the reverberation of the room.
I've attached also a picture with a graph of RT60 of right channel (RT60 is the time required for reflections of a direct sound to decay by 60 dB below the level of the direct sound.)
Then I perceived a greater involvement with the voices, thanks the great detail and dynamics.
In conclusion, the My_Ref_FE have really satisfied me, the transition from gainclone was not a side-grade, as initially thought.
Thanks,
Roberto
Attachments
Hi Roberto,
thanks for the feedback.
Do you have any pic of the interior or of the build process?
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